A light-emitting element such as a light emitting diode (referred to as “LED” in the following) or semiconductor laser has been used, e.g., as a light source for a liquid crystal backlight, an indicator, a display, and a read sensor.
For example, JP 10(1998)-62786 A discloses the invention that relates to a LED light source in which a plurality of LED chips are connected in series via wires. FIG. 9A is a schematic perspective view of the LED light source of JP 10(1998)-62786 A, and FIG. 9B is a perspective plan view of the same.
In the LED light source 100 of FIG. 9A, conductor patterns 102 are formed on a base material 101, and a plurality of LED chips 103 are die-bonded to the conductor patterns 102 and connected in series via wires 104.
However, as shown in FIG. 9B, each of the wires 104 extends from the LED chip 103 to the conductor pattern 102 in the same direction when viewed perpendicularly to the base material 101. Therefore, shadows of the wires 104 overlap while light emitted from each of the LED chips 103 is condensed by a condenser lens. As a result, luminance nonuniformity is likely to occur on an irradiation plane.